Last week, a complete Mayan city was excavated on Mexico’s Yucatan Peninsula. According to archaeologists with Mexico’s National Institute of Archaeology and History, roughly 35,000 people inhabited the site from 600 until 900 A.D, or the Late Classic Maya period, which occurred not long before the culture inexplicably vanished from the face of the earth.

The site, which covers roughly 54 acres, was named ‘Chactun’, or ‘red rock’. The findings include 15 pyramids, one of which reaches a height of 75 feet, as well as several plazas, courts, residences, religious altars, and sculptures. Several walls with hand-drawn inscriptions were also uncovered and turned over to professional epigraphers for analysis.

“It is one of the largest sites in the Central Lowlands,” said archaeologist Ivan Sprajc during an address for Mexico’s National Institute of Anthropology and History (INAH). “We realized, with big surprise, that the site was even larger than we had expected. What impressed us most were the volumes of the buildings — they are not extremely high, but very massive.”

However, Sprajc noted that he and his team were probably not the first group to uncover Chactun. “Lumberjacks and gum extractors were certainly already there, because we saw cuts on the trees,” Sprajc told Reuters. “What happened is they never told anyone.”

Numerous Mayan sites have been discovered throughout the Yucatan; some of the most notable findings include Tikal, Chitchen Iza, and Isla de Jaina. However, experts have yet to nail down the cause of the Mayan disappearance. Various theories attribute the culture’s decline and eventual eradication to factors like overpopulation, disease, and climate change. This mystery inspired the Archaeological Reconnaissance Project, which was launched in 1996; since that time, more than 80 sites uncovered by ARP participants.

While archaeologists aren’t yet sure if Chactun will shed any light on this particular conundrum, they have already learned new facts about the Mayan people thanks to numerous monuments found throughout the city, including religious altars and nearly two dozen stelae (tall shafts sculpted from stone). These items are common to Mayan ruins, but epigrapher Octavio Esparza Olguin from the National Autonomous University of Mexico told Discovery News that evidence suggests the monuments at Chactun were actually erected and used repeatedly by later generations — something he and other epigraphers have never before encountered at Mayan ruin sites.

We know what you’re thinking, and we were wondering as well… but at this time, no rolling boulders, shooting darts, or other booby traps have been reported at the site. Yet.